Example of Mood’s Median Test

An environmental scientist wants to determine whether temperature changes in the ocean near a nuclear power plant affect the growth of fish. The scientist randomly divides 25 newly hatched fish into four groups and places each group into a separate, simulated ocean environment. The simulated environments are identical except for temperature. Six months later, the scientist measures the weights of the fish. To determine whether the median weight of the fish differs among the four groups, the scientist uses Mood's median test.